message timing problems

[ursaminor]

Hi,

We've used the setup described above. Please describe what's not clear about it.

In short:

We wired the USRP output to a scope. We wired a 1 pps to the scope. There is a 2.6 us delay between them when we schedule the signal on a time rounded to a second.

We've used the 1pps of a second USRP, a different GNSS receiver, and the USRP that sends the signal (using a splitter).

The VI attached in the third post was used. It's one of the examples, modified to send messages each few seconds.

So this gives a 2.6 us delay when the 1.3 USRP driver is used, but no delay (<100 ns) when the 1.2 or 14 USRP driver is used.

Regards,

Wiebe.

[B_Sherm]

Wiebe,

I was not able to reproduce the error yet. I was having problem getting a solid GPS connection but did not see a delay when it worked for a short time. 

I want to confirm a few things.

1) Moving to USRP 14.0 seemed to fix the problem? (so far that is) Even though you were using two of the same USRP 2930s? 

2) Did you update the firmware when you went to 14.0?